Drawbridge



3, 1968 N. R. GUILBERT, JR 3,396,822

. 3 Sheets-Sheet 1 Filed March 2, 1967 INVENTOR. NICHOLAS R. GUILBERIJJR ATTOQNLZX-L Aug. 13, 1968 N. R. GUILBERT, JR 3,

DRAWBRIDGE Filed March 2, 1967 s Sheets-Sheeta FIG. 2

rron/var NICHOLAS Rica/Lemme.

1968 N. R- GUILBERT, JR 3,396,822

DRAWBRIDGE Filed March 2, 1967 3 Sheets-Sheet 3 H FIG. 5

1:! 6/ INVENTOR.

NICHOLAS R. GU/LBERT. JP.

ATTORNEY United States Patent ABSTRACT OF THE DISCLOSURE A drawbridge for dumbwaitersand elevators hingedly carried by the car with positive cam control on the car for elevating the drawbridge and auxiliary elevating and closing rollers on the drawbridge for car door engagement. v

Field of the invention This invention relates to drawbridges for the cars of dum-bwaiters and elevators, and more particularly to apparatus for effecting bridging of the edges of the car and hatchway doors in open position to facilitate the removal and entry of wheeled vehicles.

It has heretofore been proposed to provide swingable bridges for the cars of dumbwaiters and elevators but these lacked positive control of the operation thereof or had other shortcomings.

-Summary of the invention It is the principal object of the present invention to provide a drawbridge swingable from an out of action position to a position for use in bridging relation above upper margins of shaftway and car doors in the open position of such doors and with controlled movement of the drawbridge.

It is a furtherobject of the present invention to provide a drawbridge having a simple but effective cam control preferably actuated by the movement of one of the car doors and with a booster action provided by one of the car doors.

Other objects and advantageous features of the inven tion will be apparent'from the description and claims.

Brief description of the drawing The nature and characteristic features of the invention will be more readily understood from the following description taken in connection with the accompanying drawings forming part thereof, in which:

FIGURE 1 is a view in perspective of the entrance of a dumbwaiter or elevator car illustrating the drawbridge of the present invention'in closed position;

FIG. 2 is a fragmentary vertical sectional view taken approximately on the line 22 of FIG. 1;

FIG. 3 is a fragmentary perspective view of a portion of the structure shown in FIG. 1 but with the drawbridge in open position;

' FIG. 4 is a horizontal sectional view, enlarged, taken approximately on the line 4-4 of FIG. 3; and

FIG. 5 is a fragmentaryrsectional view, enlarged, taken approximately on the line 55 of FIG. 4.

It should, of course, be understood that the description and drawings herein are illustrative merely, and that various modifications and changes can be made in the structure disclosed without departing from the spirit of the invention.

Like numerals refer to like parts throughout the'several views. I

Description of the preferred embodiment Referring now more particularly to the drawings, in

which a preferred embodiment of the invention is illustrated, a portion of a vertical hatchway for an elevator or 3,396,322 Patented Aug. 13, 1968 dumbwaiter is illustrated with one of a plurality of floors to which the car 11 is moved.

The hatchway can be provided at each floor access opening with pairs of hatchway doors of conventional type, and a lower hatchway door 12 is shown in lowered and open position. The details of the upper hatchway door 13 and of the operating mechanism for the doors 12 and 13 are well known and are not necessary for an understanding of the invention.

The dumbwaitercar 11 preferably is provided with a frame 14 to which are secured vertical frame channels 15. The channels 15 have front flanges 16 and are connected at the top by a horizontal frame member 17. Horizontal trackways 18 secured to the channels 15 and providing supportsfor a wheeled vehicle ,(not shown) to be moved by the car 11 may have upright spaced guide flanges 19 with flared ends 20 for guiding the wheels of the vehicle.

The car 11 is provided with car doors movable therewith, the car doors preferably each comprising an upper panel and a lower panel 26 respectively movable vertically along and retained against displacement by their sliding engagement on the flanges 16 of the frame channels 15.

The panels 25 and 26 can be of conventional type. As illustrated, the panel 25 preferably has inner and outer flat faces 27 and 28 and upper and lower marginal edges 29 and 30. The panel 26 preferably has inner and outer fiat faces 31 and 32 and upper marginal edges 33.

The lower door panel 26 preferably has a bridging extension 36 along its upper edge 33 for reducing the clearance between the panel 26 and the hatchway door 12 in open position and a similar bridging extension 37 can be provided on upper door panel 25.

The panel 25 is preferably movable upwardly and the panel 26 is preferably movable downwardly for access to and from the car 11, the panels 25 and 26 in closing relation to the car having their edges and 33 in engagement.

The car door panels 25 and 26 are preferably connected in counterbalanced relation and for this purpose chains 40 can be connected to the panel 25 by adjustable length connectors 41 engaged with the extension 37. The chains 40 extend over pulleys 42 which are rotatably carried on shafts 43 mounted on the horizontal frame member 17. The chains 40 are preferably connected at their lower ends to opposite ends of the door panel 26, as hereinafter explained.

A drawbridge 45 is provided having inner and outer floor plates 46 and 47 and side cart wheel guide flanges 48 in outwardly diverging relation beyond the end flares 20. The drawbridge 45 is pivotally mounted with respect to the frame channels 15. Bearing holders 49 welded to the channels 15 have bearing sleeves 50 and carry drawbridge pivot pins 51. The pins 51 are secured, such as by set screws 52 in connector sockets or extension blocks 53 to which drawbridge mounting arms 55 are rigidly connected. The arms 55 can be secured to the drawbridge 45 in any desired manner, such as by welding.

The pins 51 at their outer ends have secured thereto in any desired manner, such as by welding, actuator roller arms 56. The arms 56 have cam engaging rollers 57 on shafts 58 mounted thereon for engagement with plate cams 60.

The earns 60 are preferably secured to the inner face 31 of the lower panel 26, and have the ends of the chains 40 secured thereto by bolts 61.

The cams 60 each have arcuate cam edges 62 with which the rollers 57 engage, the edges being shaped as shown in FIGS. 1, 3 and 5. The cam edges 62 impel the rollers 57 to positions shown inFIG. 1 in which the drawbridge 45 is held in elevated position and to positions as shown in FIGS. 3 and 5 permit the drawbridge 45 to be lowered.

The drawbridge mounting arms 55 have roller brackets 64 adjustably mounted by bolts 65 and nuts 66. The openings 67 in the arms 55 through which the bolts 65 extend have very loose clearances to permit clamping the brackets 64 as desired. The roller brackets 64 are also held by bolts 68 engaging in internally threaded openings 70.

Shims 71 on the bolts 68 of the desired thickness for a preferred adjustment are inserted between the mounting arms 55 and the roller brackets 64.

The roller brackets 64 have rollers 72 mounted therein on shafts 73. The shafts 73 can be held in position in any desired manner such as by external cotter pins 75. Screws 76 may be employed to retain the cotter pins 75 in place. The rollers 72 are positioned to assist in the elevation of the drawbridge 45 and retention in an elevated position and for this purpose may engage the upper edge 33 of the panel 26 and also may engage the inner face 31 of the panel 26.

The mode of operation will now be pointed out.

When the hatchway doors 12 and 13 and the upper and lower panels 25 and 26 are in their open positions the drawbridge 45 is in its lowered position (see FIG. 3) for movement of the vehicle wheels (not shown) in either direction across the floor plates 47 and 46 and along the trackways 18, guided by the guide flanges 19, to position the vehicle for movement with the car 11 to the desired floor or for removal of the vehicle from the car.

The lower hatchway door 12 and lower panel 26 are effectively bridged by the drawbridge fioor plates 46 and 47.

It will be noted that the rollers 57 are positioned with respect to the cam edges 62 to permit the lowering of the drawbridge 45.

It now the upper and lower panels 25 and 26 are moved toward each other for closing by conventional panel operating mechanism (not shown), the panel 26 moves upwardly, carrying with it the plate earns 60 on each side.

As the plate cams 60 move upwardly, the rollers 57 in engagement therewith and first with the curved cam edges 62 and then with the cam plates 60 therebeyond through the roller arms 56 and the pivot pins 51 swing the drawbridge 45 upwardly to a substantially vertical position and out of the path of movement of the panel 26 and hatch door 12. This lifting movement occurs and is completed before the panels 25 and 26 meet in their closed positions.

As the panel 26 moves upwardly also, and if the drawbridge 45 has not been lifted or moved out of the path of the panel 26 by the plate cams 60, the panel 26 by its engagement with the rollers 72 completes the upward movement of the drawbridge 45.

Upon the panels 25 and 26 by their respective upward and downward movement, the drawbridge 45 upon sulficient downward movement of the panel 26 is permitted to fall from its upright position to a position for vehicle wheel travel thereover determined by the engagement of the rollers 57 with the plate cams 60. This is a reverse of the lifting operation of the drawbridge 45.

It will thus be seen that simple but effective apparatus is provided for attaining the objects of the invention, with the drawbridge 45 raised ahead of the car door panel 26 so that it will not impede the upward motion of the hatchway door 12, and is lowered in such manner as not to interfere with the motion of the hatchway door 12.

I claim:

1. In combination:

a movable car having a lower vertically movable door panel with an upper edge,

a drawbridge carried by said car having a hinged mount ing with a pivot at a fixed location on said car and movable between a lowered position in bridging relation to said door panel upper edge and an upwardly disposed position, and

members carried by and moved with said car and controlled by the positioning of said door panel controlling the position of said drawbridge free from impedance of movement of said door panel,

said members including a cam member movable with said door panel, and

a cam follower member connected to said door panel in operating relation and engaged with said cam member.

2. A combination as defined in claim 1 in which:

said cam follower member includes a lever connected to said hinged mounting and carried by said pivot.

3. A combination as defined in claim 1 in which:

said car has horizontal trackways thereon, and

said drawbridge is mounted at an end of said trackways and in upwardly disposed position obstructs said end of said trackways, and

said drawbridge is held in said position by engagement of said cam follower member with said cam member.

4. A combination as defined in claim 1 in which:

said cam member is a plate with a curved margin and is secured to said door panel,

said pivot of said hinged mounting includes hinge pins,

said cam follower member includes a lever connected to one of said hinge pins and has a cam follower roller engaged with said cam member,

an upper vertically movable door panel is provided connected in counterbalanced relation to said lower door panel by flexible connectors,

said car has horizontal trackways thereon, and

said drawbridge is mounted at an end of said trackways and in upwardly disposed position obstructs the said end of said trackways, and

said drawbridge is held in said position by engagement of said cam follower member with said cam member.

5. A combination as defined in claim 1 in which:

said cam member is secured to said door panel.

6. A combination as defined in claim 5 in which:

said cam member is a plate with a curved margin.

7. A combination as defined in claim 1 in which:

said drawbridge has rollers carried thereby engaging an inner face of said door panel in raised position of said panel.

8. A combination as defined in claim 1 in which:

said pivot of said hinged mounting includes hinge pins,

and

said cam follower member includes a lever connected to one of said hinge pins.

9. A combination as defined in claim 4 in which:

said cam member is at one side of said lower door panel,

a second cam member is provided at the other side of said lower door panel, and

a second cam follower member is provided having a cam follower roller engaged with said second cam member and in operating relation to said drawbridge.

References Cited UNITED STATES PATENTS 839,294 12/1906 Barlow l8798 1,529,122 3/1925 Fischer 187-98 2,739,354 3/1956 Pope l87-98 RICHARD E. AEGERTER, Primary Examiner.

H. C. HORNSBY, Examiner. 

